Postdoc in Theoretical Quantum Information Processing with Spin-Photon Interfaces in Silicon - DTU Electro

Are you a theorist in quantum optics or quantum information science with the ambition to chart the path from individual quantum emitters to large-scale quantum networks? In the project EQUAL (Erbium-based Silicon Quantum Light Sources), we are developing chip-scale quantum light sources with embedded quantum memories, based on erbium emitters in ultracompact, tunable silicon nanocavities. As a postdoc in our team, you will work ahead of our experiments and develop the protocols that will turn these building blocks into powerful quantum information processors.

Erbium in silicon combines compatibility with semiconductor technology, the potential for long spin coherence, and emission in the low-loss telecom C-band, but its weak optical transition calls for very strong Purcell enhancement. Our team at DTU has demonstrated silicon nanocavities with ultrasmall mode volumes and recently made them tunable using nanoelectromechanical systems (NEMS) [1]. EQUAL is a Grand Solutions Quantum project funded by Innovation Fund Denmark and brings together DTU, HZDR , Humboldt-Universität zu Berlin , and the start-ups Beamfox and Lizard Photonics.

Moving beyond probabilistic, heralded entanglement [2], we want to understand which deterministic primitives, such as spin-photon gates and Bell-state measurements, become possible at different levels of Purcell enhancement, coherence, and loss, and how they combine with entanglement purification and quantum error correction. Our recirculating quantum photonic network (RQPN) architecture [3], which connects nonlinear cavities through programmable linear circuits, together with our work on fast reconfigurable hardware [4] and open-source simulation tools [5], provides a natural starting point. Extending these ideas to EQUAL's NEMS-based meshes of cavities with embedded erbium spins is largely uncharted territory, and the open-ended scope of the work leaves room for your own ideas.